In accordance with a rapid spread of information relevant apparatuses and communication apparatuses such as a personal computer, a video camera and a portable telephone in recent years, the development of a battery to be utilized as a power source thereof has been emphasized. The development of a high-output and high-capacity battery for an electric automobile or a hybrid automobile has been advanced also in the automobile industry. A lithium battery has been presently noticed from the viewpoint of a high energy density among various kinds of batteries.
Liquid electrolyte containing a flammable organic solvent is used for a presently commercialized lithium battery, so that the installation of a safety device for restraining temperature rise during a short circuit and the structure for preventing the short circuit are necessary therefor. In contrast, a lithium battery, namely a battery all-solidified by replacing the liquid electrolyte with a solid electrolyte layer, is conceived to intend the simplification of the safety device and be excellent in production cost and productivity for the reason that the flammable organic solvent is not used in the battery.
A sulfide solid electrolyte material is known as a solid electrolyte material to be used for an all solid lithium battery. Patent Literature 1 discloses a sulfide solid electrolyte material having a specific peak in X-ray diffraction measurement; in particular, resistance to reduction is improved by using a Si element. Patent Literature 2 discloses a sulfide solid electrolyte material having a specific peak in X-ray diffraction measurement; in particular, a LiGePS-based sulfide solid electrolyte material is disclosed. Patent Literature 3 discloses a battery containing a sulfide solid electrolyte material having a specific peak in X-ray diffraction measurement. In particular, a controlling part for controlling the potential of an anode active material layer is arranged so as to prevent reduction decomposition of the sulfide solid electrolyte material and to improve the charge and discharge efficiency. Patent Literature 4 discloses a producing method for a sulfide solid electrolyte material having a first vitrification step of forming a middle body not having Li2S by adjusting the proportion of Li2S in the raw material composition.